Lennart de Nooijer

I investigate how carbon dioxide in seawater affects the formation of calcium carbonate in shells, coral, and skeletons. And how climate change can alter this process. Calcium carbonate formation becomes more difficult with higher levels of carbon dioxide: this automatically increases the acidity of the water, which dissolves calcium carbonate. At the same time, more carbon dioxide also means more carbon, a building block of calcium carbonate. For some species, a small amount of extra carbon dioxide therefore makes it easier to produce calcium carbonate. I am also studying certain sponges that do the opposite: they produce acid to dissolve coral calcium carbonate, allowing them to live in the cavities.